The present invention is generally directed to a display control system and more particularly to a display control system for use in battery-powered portable radio equipment or the like.
With the ever-increasing substitution of solid-state components for tubes in electronic equipment, electronic equipment of virtually all forms has become adapted for portable use. Because solid-state components do not require the relatively high voltages for operation as required by their tube counterparts and because the power consumption of solid-state devices is generally much lower than that required by vacuum tubes, solid-state electronic equipment is readily adapted for portable operation. In practice, it has been found that solid-state electronic equipment, such as transistor radios, may be operated for many hours when powered by self-contained depletable power sources such as batteries.
In many instances, it is necessary or desirable to provide an indication of various electronic equipment functions. For example, in a receiving device adapted to receive and/or transmit radio signals carried over a plurality of frequencies/channels, it is usually necessary or desirable to know the frequency or channel to which the receiver is tuned. Such an indicating means would be used in, for example, multiple-channel citizens band ("CB") receivers, public service ("PS") receivers, or the like. Quite often it is desirable to provide an illuminated frequency or channel display to enhance visibility, especially in the dark. The illumination may take the form of a seven-segment digital display, a plurality of lamps physically located adjacent channel-selector positions, an incandescent lamp to illuminate non-luminous channel indications, light-emitting diodes ("LED's"), segmented and dot-matrix light emitting diode displays, gas discharge tubes, fluorescent tubes or any other suitable form.
Unfortunately, however, such illumination generally presents a significant drain on the battery or other source. Practice has shown that illuminated displays often represent a greater load on the battery than the electronic circuitry of the device. As a result, when such indicators are employed in portable equipment and continuously energized, the portable equipment operating time is substantially reduced requiring frequent battery replacement or recharging.
It is therefore a general object of the present invention to provide a new and improved display control system for conserving power in portable radio equipment.
It is another object of the present invention to provide a display control system for use in a portable radio transceiver.
It is a still further object of the present invention to provide such a display control system for conserving the power of a portable radio device which is relatively simple and economical to construct and which does not interfere with the operating ease of the radio.